Water detection device for fuel line

ABSTRACT

A warning mechanism is used to indicate the presence of an impurity in a tube carrying a fluid, for example, to warn of water in a hydrocarbon fuel line. The mechanism includes a thin plastic disk which is insoluble in the fluid but soluble in the impurity, a chamber filled by the mixture after partial dissolving of the disk, and a pressure responsive transducer.

United States Patent 1191 Lewis Jan. 22, 1974 [5 WATER DETECTION DEVICEFOR FUEL 3,531,604 9/1970 Imburgia zoo/61.04 JANE 2,781,769 2/1957Reiter 337/407 X 3,014,206 12/1961 Slavin 340/229 [76] Inventor: WarrenJ.. Lewis, 132 B tannia, 2,944,125 7/1960 Oliveau 200/82 0 Meriden,Conn.,06450 2 1 d Se 21 1972 OTHER PUBLICATIONS 2] F1 6 ProductEngineering, 6/1951; Your Next Switch Se- [21] Appl. No.: 291,073lection Problem by Riche; pp. 3&4.

52 us. c1 .Q zoo/61.04, 137/67, 200/82 0, m? ExamiqePHerman "Ohavser 340/23 5 Assistant Examiner-Robert A. Vanderhye [51] Int. Cl. H01h 35/38;1-101h 35/00 [58] Field of Search. ZOO/61.04, 61.08, 61.06, 82 R, [57]ABSTRACT 200/82 C, 84 B, 84 R, 83 J, 83 R; 340/235, d h 229- 116/114 AB118 A 137/67 68- 337/407 f l 1 l t 8 Presence of an mpunty 1n a tubecarrying a fluid, for example, to warn of water in a hydrocarbon fuelline. The [56] References Cited mechanism includes a thin plastic diskwhich is insolu- UNITED STATES PATENTS ble in the fluid but soluble inthe impurity, a chamber 2,263,840 11/1941 Franck 116/114 AB filled bythe mixture after partial dissolving of the Laken X disk and a pressureresponsive transducer 3,046,369 7/1962 Hicks 200/83 R 3,472,253 10/1969Herscher et a1. 137/67 3 Claims, 5 Drawing Figures 40 39 36 I J5 a7 34PAIENTEDJAN22 I914 SHEETZUFZ W MN MN @WMM V hut WATERDETECTION DEVICEFOR FUEL. LINE BACKGROUND OF THE INVENTION The present invention relatesto warning devices and more particularly to such devices which indicatethe presence of water in a fuel line.

The presence of water in a fuel line may cause, in the case of agasoline internal combustion engine, freezing of the line or thecarburetor, or even failure of the engine. The problem may beparticularly serious in light planes or in trucks or automobiles in thewinter.

It has been suggested that a warning device to detect the presenceofwater would consist of a water absorbent material whose resistivitywould change upon absorption of water. It has also been suggested thattwo electrical conductors be separated by a water soluble materialwhich, upon dissolving, permits the conductors to touch. Both of thesedevices, however, present a danger of explosion because of using bareelectrical contacts in the presence of a hydrocarbon, such as gasoline.

It is consequently the objective of the present invention to provide awarning device to detectand indicate the presence of an impurity in aflow 'of fluid, which device has the following beneficialcharacteristics:

1. the device will be safe and not present a danger of explosion andspecifically will not use bare electrical conductors in the hydrocarbonstream;

2. the device will give a positive indication, such as a noise or light,of the presence of the water and will not use an analog gauge, which maygive indistinct or ambiguous results;

3. the device will permit a relatively convenient and inexpensivere-setting so that it will be ready to be re used;

4. the device will be relatively simple and sturdy in construction toprevent false indications and yet be relatively low in cost.

Other objectives of the present invention will be apparent from thefollowing detailed description of the inventors best mode of practicingthe invention, the written description being taken in conjunction withthe accompanying drawings.

SUMMARY OF THE INVENTION The warning device of the present inventionconsists of an instrument which may be attached to existing fuel linesor alternatively may be installed along with the installation of newfuel lines, for example, in automobiles, boats, or planes, or otherequipment using a flow of a hydrocarbon. In general, the device consistsof a tubular body having external screw threads for mounting in or neara fuel line. The bottom of the tubular body is sealed by a removabledisk held between washers. This disk is of a plastic resin film which isinsoluble in the hydrocarbon and soluble in water. A pressure actuatedexplosion proof electrical switch is positioned near the top of thetubular body. The switch operates a warning device, such as a light orbuzzer, or operates a shut-off switch.

' In one embodiment, when water dissolves the disk, thewater-hydrocarbon mixture enters the chamber with the tubular body and,by its own pressure, pushes against a piston and actuates the pressureswitch. In andrawn into the chamber from a vacuum or air line attachedto the tubular body, which vacuum or air actuates the pressure switch.

BRIEF DESCRIPTION OF THE DRAWINGS Inthe drawings which accompany thisapplication and which should be taken in conjunction with the followingdetailed description, the figures are as follows:

FIG. 1 is a side plan view, taken partly in crosssection, showing theposition of the warning device mounted in a fuel line, with the mountingand fuel line being shown in dash-dot lines. The warning device is thefirst embodiment of the present invention and is of the spring-pressuretype.

FIG. 2 is a side plan view illustrating the position of the valve in afuel line and indicating the warning system;

FIG. 3 is a side plan view, shown'mostly in crosssection, of the secondembodiment of the present invention which is also of the spring-pressuretype;

FIG. 4 is a side plan view, shown mostly in crosssection, of the thirdembodiment of the present invention which is of the non-pressure floattype;

FIG. 5 is a side plan view, shown mostly in crosssection, showing thefifth embodiment of the present invention, which is of the vacuum or airpressure type.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The overall system of thepresent invention is illustrated in connection with FIG. 2. As shown inFIG. 2, a fuel tank 10 has an opening 11 which is closed by a cap 12.For example, the fuel tank may be the gasoline tank of an automobile,tractor, boat, or other vehicle. A fuel line 13 leads from the fuel tank10 to one side of a pressure pump 14 and out of the other side of thepump. A T pipe coupling 15 attaches the warning device, which is thewarning device of the present invention, to the fuel line 13.

Two insulated electrical wires lead from the warning device 16, one ofthe wires 17. leading to a power source and the other wire 18 leading toone side of the lamp 19, which is the warning indicator. The other sideof the lamp [9 is connected by wire 20 to the power source 21. It willbe understood, however, that other types of warning indicators, forexample, buzzers, may be used in place of the lamp 19 illustrated inFIG. 2, or a shut-off switch or relay may be used instead of, or inaddition to, the warning indicator.

The warning device 16 is shown in greater detail in FIG. 1. It consistsof a cylindrical tubular body member 22 having bottomexterior screwthreads 23 which screw into one arm of the T connection 15. The bottomof the tubular body is partly closed by an integral internal circularflange (lip) 24, forming a round hole opening 25. A first washer 26 ispositioned on the inother embodiment the entering mixture lifts afloat Iwhich actuates the switch. In still another embodiment, when thewater-dissolves the'film, air or vacuum is side of the flange lip 24,the washer 26 having a central hole 27. A disk 28, of a plastic resinfilm, is positioned on the top of the washer 26. The disk 28 is backedby a second washer 29 having therethrough a central hole '30, which hole30 is smaller in diameter than the hole 27 'of the washer 26. Thewashers 26 and 29 are of a material which is insoluble in both water andthe hydrocarbon fuel and is preferably of neoprene rubber. The disk 28is preferably of poly-vinyl-alcohol film (P.V.A.)

which is water soluble, insoluble in hydrocarbons, and may be.plasticized with glycerine. That P.V.A. film is available from PolyvalCorp., New York City, or Cadillac Plastic & Chemical Co., Detroit,Michigan.

It will be understood that the dimensions set forth below are notcritical to the proper functioning of the device and the dimensions willdepend upon the size of the tubular body as well as the amount of waterwhich is desired to set off the warning. However, the dimensions setforth below have been found suitable for inclusion in a warning deviceutilized in connection with the automobile fuel line, the automobilehaving a gasoline internal combustion engine. The tubular body has aonehalf inch internal diameter forming its chamber 31. The neoprenegaskets 26 and 29 are each l/l6 of an inch thick and 2 inch in diameter.The hole 25 is A of an inch in diameter, the hole 27 is 1/8 of an inchin diameter, and the hole 30 is 0.025 inch in diameter. The plastic diskis 0.008 inch thick and 1% inch in diameter. A brass washer 32 ispositioned on top of the washer 29, the brass washer being Va of an inchthick and l inch in diameter. A steel spring 33, preferably is of aninch in diameter and of 60 pounds strength, is positioned between thebrass washer 32 and a second brass washer 34 which is at the top of thetubular body 22, the second brass washer also having a thickness of xi;of an inch and a diameter of /2 inch.

A tubular top member 35 has internal screw threads 36 which screw ontothe external screw threads at the top of the body member 22. An internalflange 37, integral with the top member 35, holds down the brass washer34. A slidable piston 38 is positioned in the top cavity of the topmember 35 and slidable in a vertical direction therein. The piston 38acts upon button 39 of the pressure responsive switch (transducer) 40which is fixed to top member 35. A suitable switch is an explosion-proofmicro-switch which is normally open, set for a pressure of 3-5 lbs. persquare inch, and is closed by upward pressure on button 39.

It has been found preferable to position the warning device in thepressure side of the fuel line and close to the pump. The pressurerequired to activate the switch and the working time may be changed byvarying the sizes of the holes in the neoprene washers and the thicknessof the film.

In operation, if water in the fuel comes in contact with the film itwill dissolve and rupture the film..The water-fuel mixture, which isunder pressure, will enter the chamber through the orifices of the bodymember and the washers and will push the piston upwards,

I thereby closing the switch contacts.

In the embodiment of FIG. 3 the body member 22 is screw-connected to acap 41. A first short rigid tube 42 connects with elongated rigid tube43 which connects with the top member 44 containing the switch 40. Asupport 45 is attached to tube 43 and has external screw threads toinstall it in a tank or fuel unit. An elongated plunger 46 is connectedto the pressure switch 40 and its shaft is guided by rings 47 and 48.When the film is ruptured by the water-fuel mixture, the bottom of theplunger 46 will descend through the film 28, causing button 57 to movedownward and closing the switch contacts of switch 40. In thisembodiment the switch is closed by downward motion of its button.

In the embodiment of FIG. 4 a float 49 is fixed at the end of a shaft50. The shaft 50 is movably guided by rings 47 and 48. The rigidelongated tubular member 51 at its lower end contains the washers andfilm described above and tubular member 51 is attached to 1 top member44. A disk 38 is slidable within the chamber of top member 44. When thefilm 28 is ruptured the entering liquid will cause a floatation of float49, pushing the shaft 50 upwards against the disk 38, which will pushupward on buttom 39, causing the contacts of switch 40 to close.

In the embodiment of FIG. 5 the body member is an elongated rigid tube52. Another tube 53 is in communication with it and fastened thereto.The tube 53, through one-way valve 54, is in communication with a sourceof air pressure or, alternatively, as a source of vacuum. A piston 55 isslidably positioned in the chamber of top member 56.

What is claimed is:

l. A warning device to detect the presence of an impurity in a liquid,comprising a body member adapted to be mounted on a container or linefor the fluid, said body member having an internal chamber, said bodymember having an orifice into said chamber, a film sealing said orifice,said film being insoluble in said fluid and solubleby said impurity,said film sealing said fluid from said chamber after mounting of saidbody member, and a pressue actuated electrical switch attached to saidbody member and positioned so that.

flow of fluid through said orifice will actuate said switch and whereinsaid body portion is cylindrical and has a bottom internal flangeforming a lip, a first washer mounted on said flange within saidchamber, said film being positioned on said washer, a second washerpositioned on said film, and a spring compressed against said secondwasher.

2. A warning device as in claim 1 wherein the holes of the washers arealigned with the hole formed by said flange, and the hole of said firstwasher is larger in diameter than the hole of said second washer.

3. A warning device as in claim 1 wherein said washers are flexible andresilient and insoluble in said liquid or said impurity.

1. A warning device to detect the presence of an impurity in a liquid,comprising a body member adapted to be mounted on a container or linefor the fluid, said body member having an internal chamber, said bodymember having an orifice into said chamber, a film sealing said orifice,said film being insoluble in said fluid and soluble by said impurity,said film sealing said fluid from said chamber after mounting of saidbody member, and a pressue actuated electrical switch attached to saidbody member and positioned so that flow of fluid through said orificewill actuate said switch and wherein said body portion is cylindricaland has a bottom internal flange forming a lip, a first washer mountedon said flange within said chamber, said film being positioned on saidwasher, a second washer positioned on said film, and a spring compressedagainst said second washer.
 2. A warning device as in claim 1 whereinthe holes of the washers are aligned with the hole formed by saidflange, and the hole of said first washer is larger in diameter than thehole of said second washer.
 3. A warning device as in claim 1 whereinsaid washers are flexible and resilient and insoluble in said liquid orsaid impurity.